Sha256: 4685b794498870f1e2c89ed34bbf024389eaa570111295170f5396993a52d1c0
Contents?: true
Size: 639 Bytes
Versions: 396
Compression:
Stored size: 639 Bytes
Contents
#lang racket
(provide allergic-to? list-allergies)
(define allergies
#hash(("eggs" . 1)
("peanuts" . 2)
("shellfish" . 4)
("strawberries" . 8)
("tomatoes" . 16)
("chocolate" . 32)
("pollen" . 64)
("cats" . 128)))
(define codes
(for/hash ([(k v) (in-hash allergies)])
(values v k)))
(define (has-bit? n m)
(> (bitwise-and n m) 0))
(define (allergic-to? name code)
(has-bit? (hash-ref allergies name 0) code))
(define (list-allergies n)
(for/list ([(code name) (in-hash codes)]
#:when (has-bit? code n))
name))
Version data entries
396 entries across 396 versions & 1 rubygems